In conventional electronic commerce, a terminal of a customer has been required to be capable of communicating with a commerce server during the period from the start to end of the commerce.
On the other hand, a mobile terminal is characterized in that it is normally not connected with a mobile communications network so as to reduce electric power consumption as well as promoting effective use of radio resources, and is connected to the network at an arbitrary time and place in response to a call from a base station or at its user's request.
In the case of conducting electronic commerce by use of a mobile terminal, the mobile terminal may be connected with a mobile communications network only for the duration required in the electronic commerce such that a user can order an article before moving and receive the article at the place where he/she has gone.
Besides, a mobile terminal is frequently disconnected form a mobile communications network unexpectedly.
FIG. 1 is a diagram showing the configuration of a conventional electronic commerce system using a mobile terminal. FIG. 2 is a sequence diagram showing the sequence of operation of the electronic commerce system depicted in FIG. 1. In FIG. 2, a mobile terminal of a customer is connected to a commerce server at the commencement of electronic commerce. Thereafter, the electronic commerce is conducted.
After the electronic commerce is initiated (step S21), the commerce server successively requests relevant information from the user of the mobile terminal (step S22). In response to the requests, the mobile terminal transmits information input by the user to the commerce server (step S23).
By repetition of such communication exchanged between the commerce server and the mobile terminal, the electronic commerce is concluded (step S24).
As just described, in the conventional electronic commerce, the mobile terminal needs to remain connected with the commerce server all through the period from the start to end of the commerce.
Japanese Patent Application laid open No. 2000-196678 has disclosed “System and Method for Radio Data Communication Considering Disconnected Time” as a conventional technique for continuing data communication processing in a center even when data communication is cut off due to line disconnection.
In the conventional technique, data communication processing is continued in a center by acquiring beforehand a period of time in which data communication stops.
According to the technique, however, a period of time in which data communication stops has to be acquired in advance. Consequently, it is difficult to continue data communication processing in a center when line disconnection takes place unexpectedly.
As mentioned above, communication through a mobile communications network is unstable as compared to that through a wired network. Therefore, communication can be cut off abruptly at the unexpected time.
In addition, there is no significant difference between the operation sequence of the conventional electronic commerce using a mobile terminal and that of commerce using an information processing terminal connected to a wired network. In other words, the conventional technique does not make use of the characteristic of a mobile terminal that it can be connected to a mobile communications network at an arbitrary time and place.